On Thu, Mar 16, 2023, Elson Roy Serrao wrote:
> When host sends a suspend notification to the device, handle
> the suspend callbacks in the function driver. Enhanced super
> speed devices can support function suspend feature to put the
> function in suspend state. Handle function suspend callback.
>
> Depending on the remote wakeup capability the device can either
> trigger a remote wakeup or wait for the host initiated resume to
> start data transfer again.
>
> Signed-off-by: Elson Roy Serrao <quic_eserrao@xxxxxxxxxxx>
> ---
> drivers/usb/gadget/function/f_ecm.c | 71 +++++++++++++++++++++++++++++++++++
> drivers/usb/gadget/function/u_ether.c | 63 +++++++++++++++++++++++++++++++
> drivers/usb/gadget/function/u_ether.h | 4 ++
> 3 files changed, 138 insertions(+)
>
> diff --git a/drivers/usb/gadget/function/f_ecm.c b/drivers/usb/gadget/function/f_ecm.c
> index a7ab30e..c43cd557 100644
> --- a/drivers/usb/gadget/function/f_ecm.c
> +++ b/drivers/usb/gadget/function/f_ecm.c
> @@ -633,6 +633,8 @@ static void ecm_disable(struct usb_function *f)
>
> usb_ep_disable(ecm->notify);
> ecm->notify->desc = NULL;
> + f->func_suspended = false;
> + f->func_wakeup_armed = false;
> }
>
> /*-------------------------------------------------------------------------*/
> @@ -885,6 +887,71 @@ static struct usb_function_instance *ecm_alloc_inst(void)
> return &opts->func_inst;
> }
>
> +static void ecm_suspend(struct usb_function *f)
> +{
> + struct f_ecm *ecm = func_to_ecm(f);
> + struct usb_composite_dev *cdev = ecm->port.func.config->cdev;
> +
> + if (f->func_suspended) {
> + DBG(cdev, "Function already suspended\n");
> + return;
> + }
> +
> + DBG(cdev, "ECM Suspend\n");
> +
> + gether_suspend(&ecm->port);
> +}
> +
> +static void ecm_resume(struct usb_function *f)
> +{
> + struct f_ecm *ecm = func_to_ecm(f);
> + struct usb_composite_dev *cdev = ecm->port.func.config->cdev;
> +
> + /*
> + * If the function is in USB3 Function Suspend state, resume is
> + * canceled. In this case resume is done by a Function Resume request.
> + */
> + if (f->func_suspended)
> + return;
> +
> + DBG(cdev, "ECM Resume\n");
> +
> + gether_resume(&ecm->port);
> +}
> +
> +static int ecm_get_status(struct usb_function *f)
> +{
> + struct usb_configuration *c = f->config;
> +
> + /* D0 and D1 bit set to 0 if device is not wakeup capable */
> + if (!(USB_CONFIG_ATT_WAKEUP & c->bmAttributes))
> + return 0;
> +
> + return (f->func_wakeup_armed ? USB_INTRF_STAT_FUNC_RW : 0) |
> + USB_INTRF_STAT_FUNC_RW_CAP;
> +}
Why do we need to implement ecm_get_status if it's already handled in
composite.c now?
> +
> +static int ecm_func_suspend(struct usb_function *f, u8 options)
> +{
> + struct usb_composite_dev *cdev = f->config->cdev;
> +
> + DBG(cdev, "func susp %u cmd\n", options);
> +
> + if (options & (USB_INTRF_FUNC_SUSPEND_LP >> 8)) {
This feature selector doesn't indicate whether it's SetFeature or
ClearFeature request. ecm_func_suspend is supposed to be for
SetFeature(suspend) only. Perhaps we may have to define func_resume()
for ClearFeature(suspend)?
Thanks,
Thinh
> + if (!f->func_suspended) {
> + ecm_suspend(f);
> + f->func_suspended = true;
> + }
> + } else {
> + if (f->func_suspended) {
> + f->func_suspended = false;
> + ecm_resume(f);
> + }
> + }
> +
> + return 0;
> +}
> +
